A typical analog/digital cable television (CATV) system provides a plurality of channels, including both analog channels and digital channels, to consumers. Ideally, the analog channels should have power levels that are substantially equal in magnitude, as should the digital channels, the power levels of the digital channels being appropriately lower than the power levels of the analog channels. However, problems in the CATV system, such as defective cable, poor maintenance, and poor setup, may lead to a power-level imbalance.
In particular, an imbalance in a power level of a digital channel may result in impaired reception of the digital channel by the consumer. For example, if the power level of the digital channel is too low relative to respective power levels of a plurality of channels, a set-top box or a TV tuner may generate spurious signals when tuned to the digital channel. To improve reception of the digital channel, the imbalance in the power level of the digital channel must be first detected and then corrected through maintenance, repair, or power-level rebalancing.
Conventional methods of detecting an imbalance in a power level of a digital channel require a user to measure respective power levels of a plurality of channels, including the digital channel, by using a sweep meter or a spectrum analyzer, for example, and to then interpret the measured power levels. However, correct interpretation of the measured power levels necessitates a certain degree of experience, knowledge, and skill on the part of the user. Thus, a test device and a method enabling automatic detection of an imbalance in a power level of a digital channel are desired.
Unfortunately, existing test devices for analog/digital CATV systems, such as those disclosed in U.S. Pat. No. 7,489,641 to Miller, et al., issued on Feb. 10, 2009, in U.S. Pat. No. 7,403,486 to Flask, issued on Jul. 22, 2008, in U.S. Pat. No. 7,142,609 to Terreault, et al., issued on Nov. 28, 2006, in U.S. Patent Application Publication No. 2009/0086028 to Miller, et al., published on Apr. 2, 2009, in U.S. Patent Application Publication No. 2008/0089402 to Massey, et al., published on Apr. 17, 2008, in U.S. Patent Application Publication No. 2007/0275686 to Stevenson, et al., published on Nov. 29, 2007, in U.S. Patent Application Publication No. 2007/0121712 to Okamoto, published on May 31, 2007, and in U.S. Patent Application Publication No. 2005/0286486 to Miller, published on Dec. 29, 2005, which are incorporated herein by reference, do not provide such an automatic detection capability.